PCoelho PCoelho - 10 days ago 6
Javascript Question

Javascript sort array of objects by a boolean property

See edit at end for actual problem.

Ok, I have this scenario:

a = [false, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false]


Then if I do this:

a.sort(function(a,b){return !a && b});


It gives me this:

[false, false, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, false, true, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false]


It's sorta doing a sort... but not quite... :(

How do I sort this array?

EDIT:

If you are wondering why I did not use just a.sort() is because my actual array is of objects, not a plain array like the one I posted. The real one has elements that look like [{xx:true},{xx:false},...]

Answer
a = [false, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, true, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false];


a.sort(function(x, y) {
    // true values first
    return (x === y)? 0 : x? -1 : 1;
    // false values first
    // return (x === y)? 0 : x? 1 : -1;
});

console.log(a);

JSFiddle

You must return 0 when a and b both have same value, -1 if a is true and 1 otherwise.